An NYC man (Jack Black) lands on an island of tiny people -- and gets a wedgie from a robot -- in this updated kids' tale.

I just figured out what was wrong with the “King Kong” remake a few years ago: Jack Black should have played the beast — one that says, “Now let’s go partaaay-ahhh-yeah!”

In the 3-D comedy-fantasy “Gulliver’s Travels,” Black is shy, geeky New York City mailroom attendant Lemuel Gulliver, a guy who will never be a big shot. “We’re not on their level,” he says of the editorial staff at his newspaper. “We’re the little people.”

Gulliver gets his chance to blow up huge, though, when he is tapped by the paper’s travel editor (Amanda Peet) to go report on the Bermuda Triangle, which he sails into alone. Despite this being his maiden assignment, he has already learned the only thing you need to know about newspapering: If an editor tells you to do it, you do it.

Lumbering around the island of Lilliput, where the vaguely English, vaguely 17th-century, thumb-size citizens do speaketh in a curious manner, Gulliver is welcomed, sort of, by the royal court: “I wanted a bracelet,” complains the queen, “not a great big hairy beast.”

But this beast, unlike Kong, understands marketing. He allows Lilliput to believe that he is a leader in his own land — “President the Awesome” is his formal title — but that he doesn’t mind hanging out here, where the Lilliputians quickly build him a home and cheer his defeat of a rival little-people nation. Back home, argues Gulliver, Vice President Yoda can handle things for a while.

Black was already the world’s biggest little kid, and he might be the only actor who could have made this movie such nimble fun. No matter how thin the concept, Black always manages to make it his own. Here he helps a friendly little dude (Jason Segel) woo his fair princess (Emily Blunt) by feeding him lines from Prince (the wee royal from Minneapolis, not Lilliput), and busts out classic-rock lyrics like “War! What is it good for?

Absolutely naught!”

Whether he’s being treated as a little dolly by the giants on Brobdingnag, organizing the first-ever Lillipalooza or deploying a platoon of Lilliputian marching soldiers to work out a few knots in his back, he doth have a merry way about him.

The movie’s got elements of “Shrek” and “Night at the Museum,” but it has a much more childlike bounce to it than the latter, zinging from one silly situation to the next without a care. It simply throws us back to fairy-tale movies of the ’50s and ’60s, in which Danny Kaye could be relied upon to mug enough to earn his pay and the special effects tickled the imagination.

The Jonathan Swift novel is, except for the idea of little people at war, all but completely ignored, but Swift would have approved: His satire was full of the most up-to-the-minute jokes of 1726. Nor would the coiner of the word “yahoo” object to nonsense dialogue.

As for the main dirty joke in the movie, about an unusual fire engine, it’s straight from the book, in which Gulliver speaks of “Urine, which I voided in such a Quantity, and applied so well to the proper Places, that in three minutes the Fire was wholly extinguished.” Jonathan Swift, Jack Black — they’re just a couple of lovable whiz kids.